This is a continuation of study on cerebral hemodynamics and subarachnoid hemorrhage and the effect thereon of an alpha adrenergic blockader, a kallikrein inhibitor, a proteolytic enzyme which is beleived to inactivate the vasospastic elements in blood and the effects of sodium nitroprusside, a vasorelaxant. To date, the primary thrust of most investigations has been directed towards large vessel spasm. Since there is no unanimity on either the correlation between this phenenomena and the morbidity and mortality or on hemodynamics and the pathophysiology towards which therapy should be directed. In the experimental SAH monkey model, which this laboratory developed the objectives are: 2) to continue the study of the relative roles of the macro vs. the microvasculature in the hemodynamic catastrophe by quantitating pre and pot venous resistance changes as well as gross angiographic spasm; 2) to quantitate the effects of 4 different therapeutic approaches on cerebral heodynamics, metabolism, morbidity, and mortality.